how does tagging work?? (Can someone explain what ID3 tags are?)

[stratstrummer]

I have a lot of songs that are tagged poorly- like with the artist name in the song name field, etc...
How exactly does tagging work?
I am also assuming ID3 is a tagging feature. When I right click a song in itunes, and I click ID3 tags, what does this do? No matter which version I use, nothing happens. Any answers regarding this would be great.

[Galley]

ID3 tags are data that is stored in the file itself. This includes artist name, track name, album name, etc., but can also include cover art, URLs and lyrics.
http://www.id3.org/

[du3ce]

do the artworks take up alot of space on the ipod?

[SergeantPepper]

That would depend on the quality of the artwork but generally each one doesn't take more than a dozen kB. Compared to song that is a few MB this addition is negligible.